The invention relates to improved mechanisms for the communication of network messages between two network nodes on a physical connection being established between those nodes at a physical layer switch.
It is common practice for the release of news bulletins relating to certain events to be tightly controlled such that the bulletins are released not before a scheduled time. This is particularly well known in finance where there can be significant value in being the first to have access to information that could affect the markets. For example, news bulletins carrying the details of governmental budgets or interest rate changes by central banks are often embargoed until a predetermined time, at which point the news agencies that have been permitted to report on the event simultaneously release their bulletins into the public domain.
News bulletins are typically embargoed until a predetermined time by providing press reporters with access to the news information only within a “lock-up room” that is isolated from the outside world, with no communications being permitted from the room. Within the lock-up room, the news reporters are free to draft bulletins reporting the news event on computers provided for that purpose. However, those computers are physically isolated from public communication networks by an “air gap”. Network messages carrying the news bulletins are therefore queued for delivery at the transmit queues of the computers until, at the predetermined time, a switch is thrown and a physical connection to the news distribution network is established. Such press lock-ups are used by the Australian and Canadian governments so as to provide for a scheduled release of Federal Budget information (see http: (slash)(slash)www2b.abc.net.au/guestbookcentral/entry.asp? GuestbookID=389&EntryID=7 55777 and http:(slash)(slash)www.cbc.ca/news/background/budget2006/blog.html), as well as by the US Department of Labor.
On a connection being made from the computer to the news distribution network, the physical and logical links appropriate to the communication protocols in use at the computer must be established so as to permit the transmission of the queued messages onto the network. For example, when a computer in the lock-up room is reconnected to the outside world, the computer would typically establish a connection with a server located outside of the lock-up room and configured to provide a gateway onto the respective news provider's network. If the connection were an Ethernet connection, then a physical layer link must first be established between the computer and server, over which a logical data link can subsequently be established to the intended endpoint receiver of the messages from that computer. For 100BASE-T Ethernet, the time required to establish such a data link layer connection can be 100 ms or more.
The advent of high speed trading has meant that significant profits can be made by traders who are able to exploit microsecond advantages in the receipt of financial information. Delays of tens of milliseconds therefore represent a significant length of time. Furthermore, the physical switch by which the computers of a lock-up room are isolated from the public networks will not close all of its ports simultaneously. There is typically a random distribution in its port closure timings with millisecond order standard deviation such that the time between a given pair of ports closing can be significant. This inadvertently causes the news bulletins from the lock-up computers allocated to some news providers to be released prior to the bulletins of other providers.
There is therefore a need for an improved mechanism for the scheduled release of embargoed news bulletins, particularly those bulletins carrying financial news.